Sleep-Onset Association Disorder
Sleep-onset association disorder occurs when your child closely connects their ability to fall asleep with something in the setting (such as being held by his parent; being rocked to sleep; nursing, drinking, or eating at bedtime; watching television or even sleeping in a parent or sibling's bed). When this "something in the setting" is absent, your child cannot fall asleep. All of us wake up briefly a number of times each night, but we are usually not aware that we wake up because we fall back asleep very quickly. For children with sleep-onset association disorder, when they wake up during the night, they are unable to fall back asleep if their "something in the setting" is not present. If your child is only able to fall asleep with the help of a parent but has trouble returning to sleep after waking during the night, it is possible that they have a sleep-onset association problem.
Nighttime Eating / Drinking Disorder
Nighttime eating / drinking disorder is more common among infants and toddlers and involves the need for "excessive" nighttime feeding (often nursing or bottle-feeding) in order for the child to fall asleep or return to sleep. For infants, feeding during the night is a normal part of development. However, by the age of 5 or 6 months, most children are not drinking more than 8 ounces of fluid during the night (or nursing more than once or twice).
Limit-Setting Sleep Disorder
Limit-setting sleep disorder is more common for children who are walking, understand basic instructions and can tell you what they want/need (typically after age 2). With limit-setting problems, children refuse or stall bedtime (e.g., "I need to go to the bathroom, get a drink of water, one more hug, tell you something really, really important, etc.). They make it hard for the parent to leave their room without the child getting out of bed. Attempts to have the child return to bed may result in behavioral outbursts (e.g., crying; screaming; destruction of property or aggression).